1. Field of the Invention
The invention refers to an aircraft comprising a housing shaped as a substantially circular wing, means for generating a horizontal thrust, at least one rotor arranged in said housing, first air guiding means for controlling the air flow generated by said rotor, and second air guiding means for controlling the pitch of the aircraft.
2. Description of the Related Art
An aircraft of a similar kind has been discussed in the published European patent application EP-0393410. This aircraft comprises a vertical, ducted fan or rotor for generating a lift exceeding the weight of the aircraft in hovering flight. This rotor is arranged in a circular housing and provided with air guiding means for controlling the air flow it generates. Experiments with this type of aircraft have shown that the maximum velocity of flight in a forward direction is limited to a comparatively low value. At higher velocities an interaction between the horizontal air flow around the housing and the air flow generated by the rotor occurs, which leads to instabilities.
The air flow patterns on circular wings are not very well known and even less data is available for circular wings housing a ducted fan.